/* book.c -- 一本书的图书目录 */
#include <stdio.h>
#include <string.h>
char * s_gets(char * st, int n);
#define MAXTITL 41      /* 书名最大的长度 + 1 */
#define MAXAUTL 31      /* 作者姓名的最大长度 + 1 */

struct book             /* 结构模板：标记是book */
{
    char title[MAXTITL];
    char author[MAXAUTL];
    float value;
};                      /* 结构模板结束 */

int main(void)
{
    struct book library;    /* 把library声明为一个Book类型的变量 */

    printf("Please enter the book title.\n");
    s_gets(library.title, MAXTITL);     /* 访问title部分 */
    printf("Now enter the author.\n");
    s_gets(library.author, MAXAUTL);
    printf("Now enter the value.\n");
    scanf("Now enter the value.\n");
    printf("%s by %s: $%.2f\n", library.title, library.author, library.value);
    printf("%s: \"%s\" ($%.2f)\n", library.author, library.title, library.value);
    printf("Done.\n");

    return 0;
}

char * s_gets(char * st, int n)
{
    char * ret_val;
    char * find;

    ret_val = fgets(st, n, stdin);
    if (ret_val)
    {
        find = strchr(st, "\n");    // 查找换行符
        if (find)
            *find = '\0';
        else
            while (getchar() != '\n')
                continue;           // 处理输入行剩余的字符
    }
    
    return ret_val;
}